1. Field of the Invention
The present invention is in the field of implantable weight control devices. More particularly, the present invention is directed to a gastric balloon which has certain improved features enabling a surgeon to locate a filler valve and retrieval tabs on the exterior of the balloon with substantial ease while the balloon is in the stomach.
2. Brief Description of the Prior Art
Gastric balloons used for achieving loss of weight in extremely obese persons have been known in the prior art. All gastric balloons utilized for this purpose function on the principle that an empty bag or balloon is placed into the stomach through the esophagus. Thereafter, the bag or balloon is filled (fully or partially) with a suitable fluid, such as saline solution, through a filler tube which is inserted into the stomach through the mouth or the nose. The balloon occupies space in the stomach thereby leaving less room available for food and creating a feeling of satiety for the obese person. Clinical experience of the prior art has shown that for many obese patients the intragastric balloons significantly help to control appetite and accomplish weight loss.
Among the intragastric bags or balloons described in the prior art, one type remains connected to a filler tube during the entire time period while the balloon is in the stomach. The tube is introduced into the patient's stomach through the nostrils. Such an intragastric balloon is described, for example, in U.S. Pat. No. 4,133,315.
A second type of intragastric balloon of the prior art is placed into the stomach with the assistance of an appropriate plastic tube and usually a stylette. The balloon is filled with saline, whereafter the tube and stylette are withdrawn from the stomach. An intragastric balloon of the second type is described, for example, in UK Patent Application GB 2 090 747. The balloon of this UK patent reference, like many intragastric balloons of the prior art, is substantially spherical in configuration.
Even for the balloons of the second type, it may become desirable, from time-to-time, to add more saline in order to further expand the balloon to optimize weight control. Even more importantly, it is desirable for such balloons to become deflated through a tube before the empty balloon is removed from the stomach through the esophagus, or is allowed to pass "normally" through the digestive system.
To accomplish the foregoing, intragastric balloons of the second type are normally equipped with a self-sealing valve into which the filler tube can be inserted. One difficulty frequently encountered in the prior art is related to finding the valve when the balloon is already in the stomach and the surgeon is attempting to reinsert the filler tube for the purpose of adding or removing fluid from the balloon. Those experienced in the art will readily appreciate that a small endoscopic light which can be lowered into the stomach for the procedure causes the surface of the balloon to shine in such a manner that visually locating the valve is rather difficult and the process of searching for the valve undesirably prolongs the surgical procedure. Moreover, even after the filler valve has been visually located, it is often still difficult or awkward for the surgeon to reinsert the tube into the filler valve. This is because the balloon is slippery and positionally unstable. In other words, the usually spherical (or substantially spherical) intragastric balloons readily rotate in the stomach, so that even a slight disturbance of the balloon may place the filler valve into virtually any possible position relative to the filler tube poised to engage it.
For further and detailed information regarding intragastric balloons and related inflatable bags or the like designed for implantation into the human body, reference is made to the following patents and/or patent applications: U.S. Pat. Nos. 4,416,267; 4,485,805; 4,311,146; 4,236,521; 2,470,665; 3,046,988; 157,343; Published PCT Application No. PCT/US79/00354, and UK Patent Specification No. 1333096. The following articles or publications are also of interest: "Intragastral applizierter Ballon zur Behandlung der Adipositas", Deutsche Medizinische Wochenschrift (DMW), 1983, No. 8, page 315; "Intragastraler Appetit-depressor", Balloon Munch. Med. Wochenschrift 124 (1982), No. 2, page 39; "Der Magenballon in der behandlung der Adipositas permagna", Deutsche Medizinische Wochenschrift, 1984 No. 31/32, page 1200; "Intragastrick ballon som adipositasbehandling", UGESKY. LEGER 144/6, February, 1982, page 394; and the article by Joanne Richard titled "Gastric bubble battles bulge".
In light of the above-noted and other shortcomings of the prior art, there is a need in the art for an intragastric balloon which has a readily locatable filler valve and other improved properties. The present invention provides such an intragastric balloon.